american english - Word Stress in "It's up to you"

I watched a video on Youtube about the pronunciation of the phrase "It's up to you": https://www.youtube.com/watch?v=ZaZrkhCqWbk and it says that "up" is the stressed word.

I think that "It's" can be reduce to "ts" in fast speech. I noticed this in American movie especially with phrases such as "It's okay" (pronounced as: tsokay).

I would like to know if we need any stress on the last word the pronoun "you" or not? The video doesn't mention anything about the word "you" for me it seems that it doesn't require stress in a normal conversation.

Any suggestion appreciated. Thank you!